Blowout seal for well drilling rotaries



Dec. 11, 1945.

BLOW OUT SEAL FOR WELL DRILLING ROTARIES A. R. MIAIER 2,390,601

Q vi l 2 LL INVENTOR.

406057 ,9 MQ/EE,

Patented Dec. 11, 1945 August R. Maier, Oil City, Pa., assignor to OilWell Supply Company, a. corporation of New Jersey Application August 26,1943, serial No. 500,167

2 Claims.

This invention relates to improvements in blow out seals for welldrilling rotaries.

As disclosed in the prior patent to S. C. Fletinghofl et al., No.2,275,895, dated March 10, 1942, sealing means have been provided at thebottom of a well drilling rotary to prevent the ingress of foreignmatter between the rotating and stationary parts which would contaminatethe lubricating system of and injure the rotary. While the labyrinthseal of saidpatent is adequate under many operating conditions, it hasbeen found inadequate in the case of severe blow outs.

The blow out hazard is present when drilling ing the rotary lubricatingsystem eventually ruins the rotary mechanism. 7

It is the prime object of my invention to provide a positive blow outseal for a well drilling rotary which may be easily and readily applied,and which will be actuated by the force of th blow out itself to effectsuch a, seal.

Additional objects and advantages will become apparent from thefollowing description taken in connection with the accompanying drawingwherein: i

Fig. 1 is an elevational view, partly insection, showing my inventionapplied to a wel1 drilling rotary; and

Fig. 2 is an enlarged sectional view of a portion of Fig. 1,particularly showing the blow out seal.

In the drawing, the rotary includes a base 2 and a table 3 rotatablysupported thereon in the usual manner, said table being drivenbysuitable gearing including a pinion t on a shaft 5. The inner wall 6of the base 2 has a depending flange I carrying the hold-down bearing 8for the downwardly extending annularportion 9 of the table 3.

Secured to the lower end of the rotatable table forming a labyrinth seall3,v but the same does notavoidthe necessity for an outer annularcleanance opening It through which fluid under pressure may enter therotary and mix with the oil flowing in the base 2 thereof.

' To seal this opening, I provide an annular skirt i5 upon the hold-downring ill depending below and adjacent said opening i4, having its outerface recessed to contain a flexible sealing ring it of rubber or thelike. The sealing ring It extends laterally beneath and beyond theopening i4, and in close proximity to but normally out of contact withthe under surface of a portion of the stationary structure of the rotarybase, such as the retainer ring i2. The latter preferably has a smoothmachined annular face portion I! formed thereon to minimize the wearupon ring it when in contact therewith.

In operation, and in the event of a blow out in the well, the upwardlyrushing gas and foreign matter which would be directed toward openingit, strikes the flexible sealing ring l6 and dethe blow out, and whichis effective under all conditions of operation. My improved seal has theadded advantage of being readily applicable to existing rotaries bywelding or attaching the flange l5 and applying ring l6 thereto.

Various changes and modifications are contemplated within the scope ofthe following claims.

I claim:

1. In a well drilling rotary including a rotatable table and astationary base, a blow out seal therefor including a flexible sealingring secured to the lower portion of the table structure and extendinglaterally beneath and beyond the Joint between said table structure andan adjacent portion of the stationary base in proximity to the latter,said sealing ring being normally out of contact with said. portion ofthe base and actuated by the force of the blow out into sealing contactwith said base portion, and said sealing ring having a taperedcross-section terminating in a pezipheral slinging lip.

2. In a well drilling rotary including a rotatable table and astationary base, va blow out seal therefor including a flexible sealingring secured to the lower portion of the table structure and extendinglaterally beneath and beyond the joint between said table structure andan adjacent portion of the stationary base in proximity to the latter,said sealing ring being normally out of contact with said portion of thebase and actuated by the force of the blow out into sealing contact withsaid base portion said sealing ring having an outer peripheral edgeportion comprising a slinging lip for discharge of fluid therefromduring rotation of the table.

AUGUST R. MAIER.

